This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. The objective of this study is to provide protection against repeated exposure to HIV in breast milk, a neonatal HIV vaccine should elicit anti-HIV immunity at the initial site of virus exposure the oral cavity as well as throughout the infant's body. Attenuated viruses that stably express HIV proteins and replicate in the oral cavity and the gastrointestinal tract could be efficient HIV vaccines.